Determination of fluoride content in infant food samples by sample stacking capillary electrophoresis-indirect UV detection and the estimation of daily-fluoride-intake

Abstract

Fluoride ion plays a major role in the decline of the prevalence and severity of dental caries. However, exposure to a high level of fluoride causes dental and skeletal fluorosis and reduced levels of intelligence quotient (IQ) in children. This study reports a rapid, selective, sensitive, and economic capillary electrophoresis-sample stacking technique for fluoride analysis in infant food samples. Indirect UV detection of fluoride was performed by 10 mmol/L chromate in the separation electrolyte and 0.1 mmol/L cetyltrimethylammonium bromide (CTAB) was added to the separation medium as an electroosmotic flow modifier. The buffer pH was adjusted to 9.37. The conductivity of the separation electrolyte was increased with 10 mmol/L Na2SO4 and sample stacking was performed. The injections were administered throughout 200 s duration. The limit of detection of the method was 0.0079 mg/L. The method was applied to 7 various commercially available infant food samples which are in puree and powdered form. The fluoride concentrations ranged from 2.28 – 3.85 µg fluoride/g infant food. The proposed method is suitable for the rapid and sensitive determination of fluoride content in infant formulas, and it is recommended that fluoride content be determined by reliable methods in all commercial infant food samples.